209393139187 has 2 divisors, whose sum is σ = 209393139188. Its totient is φ = 209393139186.

The previous prime is 209393139107. The next prime is 209393139199. The reversal of 209393139187 is 781931393902.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-209393139187 is a prime.

It is not a weakly prime, because it can be changed into another prime (209393139107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104696569593 + 104696569594.

It is an arithmetic number, because the mean of its divisors is an integer number (104696569594).

Almost surely, 2^209393139187 is an apocalyptic number.

209393139187 is a deficient number, since it is larger than the sum of its proper divisors (1).

209393139187 is an equidigital number, since it uses as much as digits as its factorization.

209393139187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2204496, while the sum is 55.

The spelling of 209393139187 in words is "two hundred nine billion, three hundred ninety-three million, one hundred thirty-nine thousand, one hundred eighty-seven".